Air brake and vehicle control



March l, 1932. yF. P. FRANKFORD 1,847,338

AIR BRAKE AND VEHICLE CONTROL -Filed July 18, 1930 ATTOFEN EYS PatentedMar. 1, 1932 UNITED STATES FRANK I. FRANKFORD, OF RIDGEFIELD PARK, NEWJERSEY AIR BRAKE AND VEHICLE CONTROL Application mea July 1s,

This invention aims to provide control means for vehicles such'as streetcars', motor vehicles and the like. One feature of invention relates tothe provision of an air 6 brake control valve having a circuit controldevice combined therewithwhich is adapted to interrupt transmission ofpower to the vehicle simultaneously with the application of the airbrakes.

The invention will be fully apparent from the following speciicationwhen read in connection with-the accompanying drawings and will bedefined with particularity in the ap'- pended claims.

vIn the drawings z` f Fig. l is a vertical section illustrating certainparts of a street car showing one embodiment Aof my invention vappliedthereto; Fig. 2 is an enlarged longitudinalv vertical section through anair brake' control valve and circuit control device. The parts beingshown in the position they occupy when the vehicle is in motion; Y

Fig. 3 is a view similar to Fig. 2 illustrating the position of theparts when the brakes are applied to stop the vehicle and interrupt thesupply of power thereto; l

Fig. 4 is a section on line 4 4 of Fig.'2 with the addition of a diagramillustratingthe vehicle motor control circuit;

Referring first to Figs. l to 4inclusive, 10 represents a street carsupported on wheels l2 in a manner well known. i l

Brake hangers 14 support brake shoes V16 which are adapted to be pressedagainst the peripheries of the wheels l2 by'a'brake beam 18 by means ofa piston, operating in a brake cylinder 20 when air is admitted thereto.

The supply of air to the brake cylinder 20`is o controlled by a valveindicated'as a whole at 22. This valve comprises a casing 24 having alongitudinally extendingchamber 26 therein within which a valve plungerindicated as awhole at 28 operates. f The lower end of chamber 26isqclosedfby a plug 30. Y Air is supplied to the valve chamber throughpipe 32 which communicates with an air reservoir 34 which may befchargedby a suitablemotor driven compresser. Y

Brake cylinder 20'is connected bymeans of 1930. Serial No. 468,860.

a pipe 34 and valveport 36 with the valve chamber26.' Spaced from theport 36 there is an exhaust port 38 having an exhaust pipe 40 connectedtherewith.

The plunger 28 includes a cylindrical por- 65 tion 40 which is ofsubstantially the same diameter as the chamber 26 so as to fbe'freelyslidable therein and yet not prevent the escape of any appreciableamounty of air pressure. The cylindrical portion is joined to a neckportion 42 of reduced diameter by means of a graduating portion 44,whose diameter increases gradually from the neck por-- tion to thecylindrical portion. At the lower extremity of theplunger, there is aring portion 46 of substantially the` same diameter as thechamber 26. iY

A 'cavity 48 yextends a short distance longitudinally of the plunger andthis cavity communicates by means of ports 50 with the anl'm nular space52 surroundingthe neck portion and graduating portion of the plunger. nThe plunger includes an operating stem 54 `which extends through theliooring 58 of the vehicle. Normally thev operator holds his footagainst the upper end 6() ofthe stem 54 `so as to prevent passage of airfromthe reservoir 34 to the port 36 communicating with the brake pipe34. Thus, when the parts lare in the running position of Fig. 2, therewill be no supply of air to the brake cylinder. In this position, areduced portion 62 of the plunger will be opposite the brake pipe port36. Thus air from the brake cylinder can v*be exhausted through pipe 34intothe 85 space 64 between the portion 62 of the plunger kand the wallof chamber 26 'to the exhaustv pipe 40 through port 38. n

To apply the brakes, the operator gradually lifts his foot. This permitsthe air preso sure to force the plunger lupwardly toward the positionillustrated in Fig. 3. During this movement," the gradually increasingparts of the graduating portion 44 of the plunger pass the port 36 andthereby permit agrad- 95 ual application of the brakes, the air {iowingfrom the reservoir34 through pipe 32, through cavity 48 v and ports 50,to the port 36 and pipe 34 to the brake cylinder.

For an emergency application of the brakes, l

port 38.

Whenever the brakes are applied, it is ad- I vantageous tosimultaneously interrupt the supply of power to the vehicledrivenm'echanism. To this end, I provide a pair of cir- `cuit'contactfingers -65 .and 68 which are connected bymeans .of wires and l72 with avehicle driving v.motor 741 and a .suitable source of electric current 76. .The motor 74 is .connected by wire ,78 w-ithracontact 8O of asuitv,able controller indicated 'diagrammatically at 82. The movableswitch. member 84 of this .controller is connected by wire 86 with4thecurrent supply. As/thusarranged, it will be understood `that whenthe .fingers 66 and 68 engage 'the Vmetallic stem 54 ofthe plunger, .thecircuit will be closed through .the controllerthesourceof current 76.and the .motor .74, .thus permitting the 4motor to operate. lWhen the.brakesare applied and the plunger is lifted .to .the position Aof Fig.`2, an insulated sleeve 88 surrounding a portion of thestem 54 comesinto engagement with .the contact finwgers `and thereby breaks thecircuit, thus interrupting Ythe flow of current to thev drive motor.

The contact fingers `are supported on insulators y90 which are securedby suitable screws 92 to a sleeve-like fitting .94 which is detachablysecured to the ythreaded shank 96 formed .on the upper end of valvecasing 24. The Wires V70 and 72 are .electrically connected Yto thecontact fingers 66 Aand 68 by lmeans .of binding posts y98 `and 100which -extend .through suitable insulated Abushings fitted Y withinapertures formed in the .sleeve-like kfitting .94. Y

YVhileit is not essential to .the operation of the device, I provide alight `spring 148 between the lower end/of the `valve plunger .and theplug '30. This serves asa yielding stop for ythe downwardy movement .ofthe plunger, the spring being adapted -to go practically solid .upon.the limit of downward move- .mentof the plunger. c

While I .have described` with great particularity the specificembodiments .of .the invention -herein illustrated itis not to beconstrued that :I Vam limited thereto since changes in arrangement andlsubstitution of .equivalents vmay bemade by those skilled in the :artwithout departingy from the invention as delined inthe appended claims.

`What I claim is: f1. An air .brake kcontrol valve of the class fitting.

Yand `a brake cylinder, said plunger having fingers arra-nged-forengagement with a por- Y tion of said plunger, a fitting secured tothe casing `for 'supporting said contact fingers ,and meansforinsulating the'latter from said 3. .A device of the characterdescribed comprising a .chambered casing having Vports therein, -ametallic plunger :controlling the passage .of fluid through said ports,contact fingers arranged for engagement with a portion of said plunger,a fittingl detachably secured to said casing, insulators secured to vthefitting, means for securing the contact fingers to said insulators.

4. In an apparatus of the Vcharacter described, a valve casing havingachamber extending longitudinally thereof, a valve .plunger movablevaxially of said chamber, a duct adapted to communicate with a vsourceof fluid pressure and with one end of vsaid chamber `so `that lthepressure will tend to rforce said plunger `toward the oppositeV endthereof, respective ports in said chamber adapted to communicate withatmosphere one portion ysubstantially the same diameter 'as lsaidchamber-andfother'portions of smaller diameter adapted -to be broughtinto juxtaposition to said'ports to permit passage offiuid through them,yone of the portions 'ofsmaller .diameter being in communication withithe end of the chamber `which is adapted to communi'cate with said'source of fluid pressure.

f5. In lan Yapparatus of the class described a valve casing having achamber extending longitudinally thereof,- a 'valve plunger movableraxially ,of said chamber, a duct adapted to communicate with Athesource of fiuid pressure `and with one end of said chamber Viso. thatthev pressure tends 'to force said l plunger'toward the opposite endthereof, re-

fspective Aports in saidV chamber adapted to communicate with atmosphereand abrake '.cyl'inder, said plunger having one portion 1.20

.substantially the same diameter as said cham- Vber and other portionsof smaller diameter adapted to be brought vinto juxtaposition to saidports to permit passage of fluid through them, a manually operable stemsecured to said plunger and extending through an opening inthe casing.`

6. An air brake control valve of the class described comprising a lvalvecasing having a substantially cylindrical chamber therein v `spacedports opening lnto the chamber, a

plunger movable axially of the chamber, and having a substantiallycylindrical portion which makes a sliding engagement with the Wall ofthe chamber and a neck portion of reduced diameter connected with thecylindrical portion by a graduating portion Whose diameter increasesgradually from thatV of the neck portion to that of the cylindroalportion, the Space surrounding said neck portion communicating with oneend of said chamber.

In Witness whereof, I have hereunto signed my name.

FRANK P. FRANKF ORD.

